#ChangeTracking

Track changes in your POCO objects, and in your collections. By using Castle Dynamic Proxy to create proxies of your classes at runtime, you can use your objects just like you used to, and just by calling the AsTrackable() extension method, you get automatic change tracking, and cancellation.

All trackable POCOs implement IChangeTrackable<T>, IRevertibleChangeTracking, IChangeTracking, IEditableObject and INotifyPropertyChanged.

And all trackable collections implement IChangeTrackableCollection<T>, IBindingListICancelAddNew, IList<T>, IList, ICollection<T>, ICollection, IEnumerable<T> and IEnumerable

Installation

PM> Install-Package ChangeTracking

Example

###To make an object trackable

usingChangeTracking;//...Orderorder=newOrder{Id=1,CustumerNumber="Test",Address=newAddress{AddressId=1,City="New York"},OrderDetails=newList<OrderDetail>{newOrderDetail{OrderDetailId=1,ItemNo="Item123"},newOrderDetail{OrderDetailId=2,ItemNo="Item369"}}};OrdertrackedOrder=order.AsTrackable();

And here is how you get to the tracked info.

vartrackable=(IChangeTrackable<Order>)trackedOrder;// same asvartrackable=trackedOrder.CastToIChangeTrackable();

And here is what's available on trackable.

//Can be Unchanged, Added, Changed, DeletedChangeStatusstatus=trackable.ChangeTrackingStatus;//Will be true if ChangeTrackingStatus is not UnchangedboolisChanged=trackable.IsChanged;//Will retrieve the original value of a propertystringoriginalCustNumber=trackable.GetOriginalValue(o =>o.CustumerNumber);//Will retrieve a copy of the original itemvaroriginalOrder=trackable.GetOriginal();//Calling RejectChanges will reject all the changes you made, reset all properties to their original values and set ChangeTrackingStatus to Unchangedtrackable.RejectChanges();//Calling AcceptChanges will accept all the changes you made, clears the original values and set ChangeTrackingStatus to Unchangedtrackable.AcceptChanges();

By default complex properties and collection properties will be tracked (if it can be made trackable) as well. if you do not wish to track them you can set it when creating the trackable.

vartrackable=order.AsTrackable(makeComplexPropertiesTrackable:false);

or

vartrackable=order.AsTrackable(makeCollectionPropertiesTrackable:false);

###And on a collection

varorders=newList<Order>{newOrder{Id=1,CustumerNumber="Test"}};IList<Order>trackableOrders=orders.AsTrackable();

And here is how you get to the tracked info.

vartrackable=(IChangeTrackableCollection<Order>)trackableOrders;// Same asvartrackable=trackableOrders.CastToIChangeTrackableCollection();

And here is what's available on trackable.

// Will be true if there are any changed items, added items or deleted items in the collection.boolisChanged=trackable.IsChanged;// Will return all items with ChangeTrackingStatus of UnchangedIEnumerable<Order>unchangedOrders=trackable.UnchangedItems;// Will return all items that were added to the collection - with ChangeTrackingStatus of AddedIEnumerable<Order>addedOrders=trackable.AddedItems;// Will return all items with ChangeTrackingStatus of ChangedIEnumerable<Order>changedOrders=trackable.ChangedItems;// Will return all items that were removed from the collection - with ChangeTrackingStatus of DeletedIEnumerable<Order>deletedOrders=trackable.DeletedItems;// Will Accept all the changes in the collection and its items, deleted items will be cleared and all items ChangeTrackingStatus will be Unchangedtrackable.AcceptChanges();// Will Reject all the changes in the collection and its items, deleted items will be moved back to the collection, added items removed and all items ChangeTrackingStatus will be Unchangedtrackable.RejectChanges();

Requirements and restrictions

• .net 4 and above

#####For Plain objects

• Your class must not be sealed and all members in your class must be public virtual

  publicclassOrder{publicvirtualintId{get;set;}publicvirtualstringCustumerNumber{get;set;}publicvirtualAddressAddress{get;set;}publicvirtualIList<OrderDetail>OrderDetails{get;set;}}

#####For Collections

• You can only assign the created proxy to one of the implemented interfaces, i.e. ICollection<T>, IList<T> and IBindingList, and the AsTrackable<T>() will choose the correct extennsion method only if called on IList<T>, IList, ICollection<T> and ICollection.

  IList<Order>orders=newList<Order>().AsTrackable();